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Finding the Fourth Proportional to 678.92, 937.12 and 399.17

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Solution

The fourth proportional to 678.92, 937.12 and 399.17 is: 550.98

Step by Step Solution

  1. Step 1: Write the proportion equation
    678.92 : 937.12 = 399.17 : x
  2. Step 2: Convert to fraction form
    678.92/937.12 = 399.17/x
  3. Step 3: Cross multiply
    678.92x = 937.12 × 399.17
  4. Step 4: Simplify right side
    678.92x = 374,071.54
  5. Step 5: Solve for x
    x = 374,071.54/678.92
  6. Step 6: Final answer
    x = 550.98

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.